Under some scenarios, a group of users of PTT radios connected to one PTT system desire to communicate with a group of users of PTT radios connected to a disparate PTT system. Due to differences between group management methods and call control protocols of various PTT systems, bridging techniques implemented in a bridging gateway are used to facilitate calls between the groups on disparate PTT systems. However, the known bridging techniques do not work in all cases, especially in the case where the group call control signaling received at the bridging gateway does not provide a group identifier for the group in the first system to enable the bridging gateway to determine the targeted group in the other PTT system.
Thus, there exists a need for a novel method and apparatus for bridging calls between two disparate PTT systems.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. In addition, the description and drawings do not necessarily require the order illustrated. It will be further appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. Apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the various embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Thus, it will be appreciated that for simplicity and clarity of illustration, common and well-understood elements that are useful or necessary in a commercially feasible embodiment may not be depicted in order to facilitate a less obstructed view of these various embodiments.